Cytotoxic testing for food allergy: evaluation of reproducibility and correlation.

Cytotoxic food tests still present conflicting opinions concerning their validity. Nine atopic patients with or without a history of food allergy were studied along with 5 nonatopic patients. All tests were conducted in a double-blind fashion with 6 determinations for each of 10 food antigens. Reproducibility of the test (5/6 positive or negative) was demonstrated with wheat, milk, yeast, chocolate, and orange. In the nonatopic group, reproducible results were obtained for wheat, egg, yeast, chocolate, and chicken. Clinical correlation with 11 foods in 7 patients was demonstrated. However, there were 46 positive tests without correlation and 2 negative tests with positive histories. Therefore, there appears to be reproducibility of the tests to only 3 foods but no apparent correlation with clinical symptoms. At the present time, cytotoxic tests offer no reliable help in establishing the diagnosis of food allergy.